On Friday, February 9, 2024 at 10:18:45 AM UTC+9 Travis Scrimshaw wrote: I would be vague about a TypeError versus a ValueError. These are used in various ways by different authors over different periods.
Helping an author in choosing the most appropriate one among sometimes confusing array of Exceptions is the aim of my proposal. It would be impossible to write a guide consistent with existing code in sage. It is forward-oriented. No plan to update sage code according to the guide. It can also be very hard to make this rigorous. TypeError and ValueError is the most confusing case. Python documentation does not help much. Giving a rough definition in sage context would be helpful. For example, for something accepting integer inputs, then 2/2 fails the isinstance() check but shouldn't throw an error. Likewise 1/2 is a bad value that cannot be tested by the isinstance() check alone. Actually, I might consider putting them together and letting the programmer decide which is most appropriate (of course, there are clear cases, such as a list compared to a number). Sorry, I should not have used "isinstance()". I wanted to emphasize that TypeError should be used to reject input objects in certain "type" or "class" or "set" For example, if a method accepts a polynomial as input. Then it may emit TypeError because the input is a polynomial over symbolic ring while it may emit ValueError because the specific input is not appropriate for the method to work. Of course, if the input is not a polynomial, this is just user's fault (no need to detect this in general) Right, there is no perfect or rigorous definition. But we may give a certain guide or hint with which the author chooses an appropriate one between TypeError and ValueError. In the order of specificity, INPUT description > TypeError > ValueError > ArithmeticError > ZeroDivisionError If no other type of error is appropriate, then RuntimeError. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/f951ccd8-439d-4810-b425-f637d5bd67a2n%40googlegroups.com.
